KR101553814B1 - Self-adhesive protection film - Google Patents

Abstract

The present invention relates to a self-adhesive protection film which comprises a skin layer, a core layer, and an adhesive layer, wherein the skin layer is formed with an organic resin, and the surficial roughness (Ra) of the outer surface of the skin layer is 100 to 900 nm.

Description

{SELF-ADHESIVE PROTECTION FILM}

The present invention relates to a self-adhesive protective film for protecting the surface of a sheet / film used in optical and industrial applications.

Functional protective films are attached to PET, PC, PMMA and glass which are used as optical sheets, ITO and industrial sheets to prevent surface damage due to foreign matter, contamination and scratches that may occur during process and shipment.

Blown type self-adhesive films using EVA have been used. However, such protective films have a problem in that the adhesive strength of the protective film is deteriorated due to a change in the adhesive strength with time, a fish eye in the film, Quality problems such as line transfer, transfer due to pressure-sensitive adhesive, and residue are caused due to wrinkles and thickness variations during lamination due to pressing and thickness variations

For example, the protective film is usually wound in a roll state for storage and transportation, and then the protective film roll is used to release it. Therefore, the opposite side to the adhesive side is brought into contact with each other, so that the releasability should be good in the process of unwinding the protective film roll. Therefore, in general, the protective film is formed by forming a pressure-sensitive adhesive layer having a tacky surface on one side thereof in order to provide an adhesive force with the adhered film, a core layer for providing tensile strength, elongation and rigidity for maintaining the shape of the protective film, And a skin layer that provides anti-blocking and releasability with the layer.

At this time, the skin layer is used by adding a large amount of an anti-blocking agent (anti-blocking agent), a release agent, etc. to the resin forming the skin layer in order to prevent blocking and releasability. In particular, the amount of these additives to be added is higher in a high-adhesive protective film having a high adhesive strength of the adhesive layer.

On the other hand, when the fish eye is present in the film at a level higher than a certain level, the protective film can not be used and treated as defective. Such a protective film is known to be affected by low-molecular substances present in the resin used. Accordingly, the development of technology has been proceeding in the direction of suppressing the production of fish eyes through removal and dispersion of low-molecular substances present in the resin.

According to the studies of the present inventors, it has been confirmed that such fish eyes are greatly affected not only by the quality of the resin used but also by the additives added for imparting the functionality of the protective film.

Therefore, it is an object of the present invention to provide a protective film in which the presence of fish eyes is suppressed while securing the function of anti-blocking and releasability required for the protective film.

An embodiment of the present invention is to provide a protective film capable of reducing the production cost of a product by significantly reducing the defective product due to fish eye by suppressing the occurrence of fish eyes.

The present invention provides a self-adhesive protective film. According to one embodiment of the present invention, there is provided a self-adhesive protective film comprising: a skin layer; A core layer; And a pressure-sensitive adhesive layer, wherein the skin layer is made of an organic resin, and the outer surface of the skin layer has a surface roughness (Ra) of 100 to 900 nm.

According to another embodiment of the present invention, A core layer; And an adhesive layer, wherein the skin layer has a surface roughness (Ra) of less than 100 nm on the outer surface of the skin layer, and the skin layer comprises an organic resin; And at least one additive selected from the group consisting of a releasing agent and an antiblocking agent.

The organic resin paper of the skin layer may be a polypropylene resin or a mixed resin of polypropylene and polyethylene in a weight ratio of 97: 3 to 55:45.

The polyethylene may be at least one selected from the group consisting of low density polyethylene, linear low density polyethylene and high density polyethylene.

The additive preferably comprises 1 to 30% by weight based on the total weight of the skin layer. More specifically, the additive may include 1 to 30% by weight of a release agent and 0 to 29% by weight of an antiblocking agent.

The release agent may be a silicone release agent or a siloxane release agent and the antiblocking agent may be at least one selected from calcium carbonate (CaCO ₃ ), talc, silica (SiO ₂ ), aluminum silicate, silicon beads and PMMA.

The additive preferably has an average particle size of 20 mu m or less (excluding 0).

The core layer comprises at least one resin selected from the group consisting of polypropylene and polyethylene.

The adhesive layer comprises at least one resin selected from the group consisting of a linear low density polyethylene, a metallocene linear low density polyethylene, a metallocene polyethylene and an elastomer.

According to the present invention, generation of fish eyes is remarkably improved, and the defect rate of the product can be reduced, thereby reducing the production cost of the product.

In addition, the releasability can be realized by using the surface roughness (100 to 900 nm) of the resin itself without using a release agent or an antiblocking agent.

Hereinafter, the present invention will be described in detail.

The protective film provided by the present invention has a structure in which a skin layer, a core layer and a seal layer are sequentially laminated.

The skin layer of the present invention can use a polypropylene resin as a resin for forming a skin layer. The polypropylene resin has a rigid property and can be suitably used as a skin layer.

Such a polypropylene resin is not particularly limited as long as it can be suitably used in the present invention as long as it is generally used as a skin layer of a pressure-sensitive adhesive protective film. Examples thereof include propylene homopolymer and propylene, Butene, 1-hexene, 1-octene and the like, or a propylene copolymer obtained by copolymerizing at least one of alpha-olefins of 4 to 20 carbon atoms. More preferably, the polypropylene block copolymer has a high surface roughness and is advantageous in releasability and releasability of the skin layer, and it is more preferable to use a polypropylene block copolymer.

The skin layer may further include a polyethylene resin in the polypropylene resin. The polyethylene resin has a soft characteristic, so that the skin layer can be softened to further increase the adhesive force. The polyethylene resin is not particularly limited, but low-density polyethylene can be used. Examples of the low-density polyethylene include the products 531G and 642M of Samsung Total Co., Ltd. or BF415 of LG Chemical Co., Ltd. However, the low-density polyethylene is not limited thereto.

When the polyethylene resin is included, low haze characteristics can be imparted to the skin layer. It is preferable that the polypropylene resin and the polyethylene resin are mixed so as to have a weight ratio of 97 to 55: 3 to 45. When the polyethylene resin is mixed with less than the above-mentioned weight ratio, the softening property of the skin layer due to the mixing of the polyethylene resin is insignificant, so that it does not contribute to the improvement of the adhesive strength.

On the other hand, the polyethylene resin has a characteristic that the surface roughness is relatively low. When polyethylene is mixed in an excess amount exceeding the weight ratio, the surface roughness of the skin layer is small and sufficient releasability and releasability can not be secured. Particularly, when a polyethylene resin is mixed, it is blended with polypropylene to disperse the surface roughness of the polypropylene to obtain a uniform and similar roughness, and the haze can be lowered compared with polypropylene alone. Further, when polyethylene is used as the main resin of the core layer, compatibility with the skin layer including polyethylene is excellent, and the problem of delamination can be solved, which is preferable.

The polyethylene resin to be mixed with the polypropylene resin of the skin layer may be a low density polyethylene resin as described above, but a high density polyethylene resin may be used, or a mixture of low density polyethylene and high density polyethylene may be used. Such high-density polyethylene can be suitably used in the present invention as long as it is generally used, and is not particularly limited.

The high-density polyethylene resin provides heat resistance to a film, and adhesion between films can be prevented during storage in a roll state. When a high-density polyethylene resin is included, it is possible to improve the phenomenon that the cross-section between the protective films is melted by heat even when the protective film is attached to the adhered sheet and processed into a smaller size after cutting and stacking .

In general, the protective film is rolled into a rolled state and stored and transported, and the user releases the protective film in use. Therefore, the skin layer is in contact with the adhesive layer having self-adhesive property, so that blocking can be suppressed and the releasability of the skin layer can be secured. For this reason, additives such as release agents and antiblocking agents (anti-blocking agents) have generally been added to resins for skin layer production in order to inhibit blocking and to ensure releasability.

However, such an additive may act as an impurity in the resin and adversely affect the quality of the protective film. For example, the release agent may cause local peeling between films in producing the film by co-extrusion. The anti-blocking agent is added to form a protrusion on the surface of the skin layer in order to provide releasability. The protrusion pushes the surface of the film stored in the roll state to transfer the protrusion form to deteriorate the appearance quality, It may cause problems such as generation of pressing marks on the sheet and the like.

In addition, these additives act as a cause of producing fish eyes in the film to produce a large fish eye or increase the number of fish eyes. The inventors of the present invention have found that additives such as releasing agents or antiblocking agents added to improve the releasability of the skin layer and to prevent blocking during the research of the protective film for the purpose of improving the defective product due to the occurrence of fish eyes, Found that it was an influential factor.

The reason for this is not clear, but when the mold release agent or the antiblocking agent is contained in the resin, these additives act as impurities in the resin, and it is considered that causing the flocculation of the resin around these additives causes the formation of fish eyes. Therefore, it is preferable that such an additive is not included in order to suppress fish eye formation.

However, when the mold release agent or the anti-blocking agent is not added, the skin layer is brought into contact with the adhesive layer during winding for storage of the film, and blocking and loosening are deteriorated due to adhesiveness of the adhesive layer, As shown in FIG. Accordingly, the present inventors have studied for the purpose of preventing blocking and improving releasability while suppressing the use of the above-mentioned mold release agent and antiblocking agent, and studied the relationship between the surface roughness and the haze of the skin layer.

As a result, it has been confirmed that good properties can be secured without adding a component acting as an impurity such as a mold release agent or an antiblocking agent by appropriately adjusting the surface roughness of the resin itself according to the haze of the skin layer.

In the self-adhesive protective film of the present invention, it is preferable that the surface roughness Ra of the skin layer has a range of 100 to 900 nm. When the surface roughness is less than 100 nm, the contact area with the adhesive layer increases and blocking with the adhesive layer may occur. As a result, the releasability is deteriorated, which may adversely affect the workability and can not be used as a protective film . On the other hand, when the surface roughness Ra is larger than 900 nm, there is a problem that the appearance of the projection-like shape becomes poor after the film is wound.

Therefore, the surface roughness Ra of the skin layer is preferably within the range of 100-900 nm, more preferably 100-700 nm.

According to another embodiment of the present invention, when the surface roughness Ra of the skin layer is less than 100 nm, blocking properties with the adhesive layer may occur as described above, and may include release agents and antiblocking agents.

However, these release agents and antiblocking agents act as impurities in the skin layer and may affect the formation of fish eyes of the film, so that they are preferably added in a minimum amount. Any of these additives may be added singly or two or more of them may be selected as needed.

The additives may include a total additive amount of not more than 30 wt% (excluding 0), based on the total weight of the skin layer. When the content of the additive is more than 30% by weight, the possibility of occurrence of fish eyes increases, and there is a high possibility that a problem of forming a low molecular substance in the lip of the pneumatic pressure extrusion die occurs.

The release agent may be a silicone release agent or a siloxane release agent alone or in combination. The silicone release agent or the siloxane release agent may be contained in an amount of 1 to 30% by weight based on the total weight of the skin layer. If the content of the releasing agent is less than 1% by weight, the releasability is deteriorated. If the content exceeds 30% by weight, the releasability is excellent, but the productivity and windability due to excessive slip property of the film may be adversely affected.

Further, the protective film of the present invention may contain the releasing agent alone in the skin layer, but an antiblocking agent may be added if necessary. The antiblocking agent can improve the blocking property with the adhesive layer by improving the roughness by roughening the roughness of the film. Examples of the antiblocking agent include inorganic agents such as calcium carbonate (CaCO ₃ ), talc, silica (SiO ₂ ), aluminum silicate, silicon beads and organic amine PMMA. These antioxidants may be used singly or in combination have.

The antiblocking agent preferably increases the content of the antiblocking agent as the adhesive strength of the adhesive layer in contact with the skin layer is higher. If the adhesive strength of the adhesive layer is high, the workability is reduced due to stickiness during the production of the protective film as well as during the production and winding of the protective film.

The antiblocking agent may be appropriately selected in a range of 29 wt% or less based on the total weight of the skin layer. If the content of the antiblocking agent added exceeds 29 wt%, transparency of the film may be decreased. Preferably 3 to 20% by weight, and more preferably 5 to 10% by weight.

The release agent and the antiblocking agent which are the additives are preferably those having a particle size of 20 탆 or less, more preferably 10 탆 or less. If the particle size of these additives is larger than 20 mu m, the large size may agglomerate with the surrounding resin, thereby increasing the amount of fish eye produced in the film. For example, the additive may be in the range of 1 to 20 mu m, more preferably the additive has a particle size of 1 to 15 mu m, 2 to 10 mu m, or 2 to 6 mu m.

In the present invention, the core layer provides tensile strength, elongation and rigidity of the entire adhesive film, and polypropylene and polyethylene can be used singly or in combination. At this time, the mixing ratio is not particularly limited, but may be mixed in a weight ratio of 95: 5 to 5:95. For example, at various weight ratios such as 95: 5, 90:10, 80:20, 60:40, 50:50, 40:60, 30:70, 20:80, 10:90 or 5:95 .

Further, the high-density polyethylene may be blended with the polypropylene, polyethylene or a mixed resin thereof, wherein the high-density polyethylene may be mixed with 5 to 95% by weight of the total weight of the core layer resin. When the high-density polyethylene is mixed, it is preferable for improving the heat resistance of the film.

The pressure-sensitive adhesive layer of the present invention is a layer which gives a self-adhesive property, and the pressure-sensitive adhesive layer can be used alone or in combination of linear low density polyethylene, metallocene linear low density polyethylene, metallocene polyethylene and elastomer.

More preferably, linear low density polyethylene, metallocene linear low density polyethylene and metallocene polyethylene can be suitably mixed and used in accordance with the required adhesive strength. The linear low density polyethylene and the metallocene linear low density polyethylene can be applied to a low adhesion protective film. However, when the high and low adhesion strength is required, there is a certain limit to the adhesive force, so that the metallocene polyethylene and the elastomer are appropriately The mixture can be adjusted to the required adhesive strength.

The mixing use of them is not particularly limited, as they can be adjusted according to the adhesive strength of the protective film to be obtained. For example, when a low adhesive force of about 100 gf / 25 mm or less is required on the basis of an adhesive force to glass, linear low density polyethylene and metallocene polyethylene can be mixed in a weight ratio of 1-99: 99-1, Rosen polyethylene and metallocene linear low density polyethylene can be mixed at a weight ratio of 1: 99: 99: 1. Further, for example, in the case where an intermediate point of adhesion of about 100-350 gf / 25 mm is required on an adhesive force basis, an elastomer can be used.

On the other hand, when the elastomer is used alone, stickiness may adhere to the roll in the curl, which may lead to a decrease in productivity. Therefore, it can be suitably mixed with linear low density polyethylene, metallocene linear low density polyethylene and metallocene polyethylene resin as a tackifier.

However, the types and mixing ratios of these resins are merely examples, and the present invention is not limited thereto, and it will be understood by those skilled in the art that various combinations are possible depending on the required adhesive strength level.

The elastomer may be selected from the group consisting of styrene-butadiene-styrene (SBS), styrene-ethylene-butylene-styrene (SEBS), styrene- (Olefin block copolymer GARDE name: INFUSE 9507, MI 5.0, density 0.866 g / cm 3) manufactured by Infusem DOW Chemical Co., Ltd., etc.) and the like These can be used alone or in combination with the main resin of the adhesive layer.

The elastomer may be appropriately adjusted according to the adhesive force required for the protective film, and is not particularly limited. For example, the elastomer may be added in various amounts within a range of 1 to 90% by weight of the total weight of the resin to control the adhesive strength.

Meanwhile, the surface self-adhesive protective film of the present invention can be manufactured by a three-layer feed block T-die cast co-extrusion method or a three-layer manifold T-die cast co-extrusion method.

On the other hand, the protective film must have a size within a certain range or no more than a certain number of pieces per unit area, even if the fish eye does not exist or exists. When a protective film is present in the protective film, the protective film affects the deposited film to which the protective film is adhered and causes surface defects. Therefore, when a fish eye of a general protective film is present, it is handled as a defect and discarded. If the number of defective protective films increases due to the presence of such fish eyes, eventually, the production cost of the protective film is increased do.

The criterion to be treated as defective due to the presence of the fish eye may vary according to the demand of the consumer, but in general, when there is at least one fish eye having a size of 0.3 mm or more in the protective film, or even if the fish eye is less than 0.3 mm, M < 2 >). Thus, it is most preferred that no fish eye be present, but if present, it should be present in a size of less than 0.3 mm, and furthermore, be present in less than 10 per unit area.

In the protective film of the present invention, the thickness ratio of the skin layer, the core layer and the pressure-sensitive adhesive layer film is not particularly limited, but is preferably in the range of 10-35%, 40-80%, 10-40%. If the thickness of the skin layer is too thin, film formation may be poor, and if it is too thick, transparency of the film may be deteriorated.

The above-mentioned pressure-sensitive adhesive film can be produced by a conventional multilayer film production method, and is not particularly limited. For example, it can be manufactured by a 3-layer T-die cast co-extrusion method. An extruder equipped with a fine filter may be used at the time of producing the film by the co-extrusion. The fine filter may be a disk type, a leaf disk type, or a wire net type, and a mesh reinforced filter may be used on one side or both sides.

Whereby the monomer contained in the resin or the low molecular weight resin can be dispersed and removed. These monomers or low molecular weight resins have a weight average molecular weight of 10,000 or less and are radicalized and reacted during melt extrusion to cause production of fish eyes. By dispersing and removing low molecular weight resins by double filtering, The generation of eyes can be suppressed.

Example

Hereinafter, the present invention will be described more specifically by way of examples. However, the following examples are provided to facilitate understanding of the present invention, and thus the present invention is not limited thereto.

Examples 1-12

As shown in the following Table 1, using a composition constituting each layer, a thickness of 40 占 퐉 composed of a skin layer, a core layer and an adhesive layer through a 3-layer Feed Block T-Die extrusion (the thickness of each layer was 6 Mu m, 26 mu m, and 8 mu m).

The haze and surface roughness of the skin layer of the protective film obtained by each example were measured, and the results are shown in Table 1.

The symbols used in the above Table 1 are as follows.

* Skin layer

-PP 1: Polypropylene. Samsung Total BF308

-PP 2: Polypropylene. Hyosung's J640F

-PP3: Polypropylene. Hyosung's J440F

-PP4: Polypropylene. Hyosung's J420HY

-PP5: Polypropylene. Samsung Total's CF309

-PE: Samsung Total's 533M

-AB: SiO ₂ , Purecom AB1105S4 (particle size 5 탆)

* Core layer

-PP: Polypropylene. Hyosung's J440F

-LDPE: Samsung Total's 642M

-HDPE: JPE's HF560

* Adhesive layer

-LLDPE: Linear low density polyethylene. LG Chem ST508

-M-PE: metallocene polyethylene. JPE KC340T

-Elastomer: Elastomer. JSR's Dynaron 8300P

-M-LLDPE: metallocene linear low density polyethylene. LG Chem's SP510

The properties shown in Table 2 were measured for the protective films obtained in Examples 1 to 12, and the results are shown in Table 2.

The measurement of each physical property was carried out as follows.

- Adhesion strength: Measured by KSA 1107 method (gf / 25 mm, 90Oeel).

- Fish eye: The naked eye was checked with a three-wavelength lamp to confirm the presence and number of fish eyes, and the size of fish eye was confirmed by microscope.

- Adhesive transfer, film transfer, stain, stop line: The PET film and the PMMA film were placed under a load of 5 kg under the conditions of a temperature of 85 ° C and a humidity of 85%, and the protective film obtained in each of the examples and the comparative examples was laminated. , Aged for 14 days, and then confirmed using a halogen lamp and a three-wavelength lamp.

- Adhesive transfer, film transfer and stain, stop line: The protective film obtained in each of the Examples and Comparative Examples was laminated on a PET and PMMA film under a load of 5 kg, aged for 14 days in a constant temperature / After that, it was confirmed by using a halogen lamp and a three-wavelength lamp. The conditions of the thermostat and the hygrostat were measured at a temperature of 40 ° C to 10 ° C and a drying condition of 80 ° C and a temperature of 85 ° C and a humidity of 85%. Observation results were recorded as poor when adhesive transfer, dye transfer, stain, and stop lines were observed even under one condition.

- Peelability: The peel strength was measured by peeling the peeled sheet after attaching the nylon tape adhered with a 5 kg roller to the skin layer of the protective film at 300 mm / min and laminating. The lower the peel strength value, the better the releasability.

Peeling strength between films: The adhesive layer and the skin layer of the protective film were laminated with a 5 kg roller at a rate of 300 mm / min, followed by laminating after 20 minutes, and peeling strength was measured. The lower the peel strength value, the better the releasability.

-Removability of unwinding state: The protective film obtained in each example was wound in a roll state, and then it was checked whether or not noise was generated when the film was unwound by hand. When the film was loosened without generating noises, Was evaluated as poor.

As can be seen from the above Table 2, when the anti-blocking agent or release agent is not added in the case of having Ra value of 100 nm or more, the number and size of fish eyes are generally satisfactory.

Furthermore, it can be seen that good releasability and releasability can be ensured for all adhesion values, even though no additive is added.

Comparative Example  1 to 5

As shown in Table 3 below, an adhesive protective film composed of a skin layer, a core layer and an adhesive layer (having a total thickness of 40 占 퐉 and a thickness of 40 占 퐉) was extruded through a 3-layer Feed Block T- The thicknesses are 6 占 퐉, 26 占 퐉 and 8 占 퐉 in this order).

The haze and the surface roughness of the skin layer of the protective film obtained by each of the comparative examples were measured, and the results are shown in Table 3.

The symbols representing the compositions used in Table 3 are as described for Table 1.

With respect to the protective films obtained in the respective comparative examples shown in Table 3, the properties of the respective protective films were evaluated in the same manner as in Example 1, and the results are shown in Table 4.

From Table 4, it can be seen that the surface roughness is improved by the inclusion of the antiblocking agent in comparison with the Examples showing similar adhesion values in the case of Comparative Examples 1 to 5, and the final winding state releasability is good and is not treated as defective, The number of eyes is increased, and the size of fish eyes is also increased.

Especially in the case of Comparative Examples 3 and 5, the number of fish eyes exceeded 10 per unit area, and the fish eyes were treated to be defective including those having a size exceeding 0.3 mm.

From the results shown in Tables 2 and 4, when the surface roughness of the skin layer is 100 nm or more, good releasability can be secured without using a mold release agent or an antiblocking agent. It is also understood that when a mold release agent or an antiblocking agent is used, the production of fish eyes of the film is caused. Therefore, in order to ensure good releasability while suppressing fish eye formation, it is preferable not to use a mold release agent or an antiblocking agent when the surface roughness of the skin layer is 100 nm or more.

Example 13, Comparative Examples 6 and 7

As shown in Table 3 below, an adhesive protective film composed of a skin layer, a core layer and an adhesive layer (having a total thickness of 40 占 퐉 and a thickness of 40 占 퐉) was extruded through a 3-layer Feed Block T- The thicknesses are 6 占 퐉, 26 占 퐉 and 8 占 퐉 in this order).

The haze and surface roughness of the skin layer of the protective film obtained in Example 13, Comparative Examples 6 and 7 were measured, and the results are shown in Table 5.

The symbols representing the composition used in Table 5 are as described for Table 1.

The properties of the respective protective films were evaluated in the same manner as in Example 1 with respect to the protective films obtained in the Examples and Comparative Examples in Table 5, and the results are shown in Table 6.

As can be seen from Table 6, the surface roughness of the skin layer of Comparative Example 6 and 7 was not 100 nm, but the surface roughness of the skin layer was 130 Nm level.

As can be seen from Comparative Examples 6 and 7, when the surface roughness of the skin layer does not reach 100 nm, it is understood that the number of fish eyes is small because no additives are included. However, since the surface roughness is small, 470 gf / 25 mm, and the peeling force between the films also showed a value of 85 gf / 25 mm, indicating that the unwinding state in the wound state was defective.

Therefore, when the surface roughness of the skin layer does not reach 100 nm, it is preferable to add an additive for a releasing agent or an anti-blocking agent to improve the surface roughness.

Claims (11)

delete Skin layer; A core layer; And an adhesive layer,
Wherein the skin layer has a surface roughness (Ra) of less than 100 nm on the outer surface of the skin layer,
An organic resin in which a mixture of polypropylene and polyethylene is mixed in a weight ratio of 97: 3 to 55:45; And at least one release agent selected from silicone release agents and siloxane release agents and at least one anti-blocking agent selected from calcium carbonate (CaCO ₃ ), talc, silica (SiO ₂ ), aluminum silicate, silicon beads and PMMA At least one additive selected from the group consisting of
The polyethylene is at least one selected from the group consisting of low density polyethylene, linear low density polyethylene and high density polyethylene,
The additive preferably has an average particle size of 20 탆 or less (excluding 0), and is in the range of 1 to 30 wt%
Wherein the protective film is a self-adhesive protective film.
delete delete delete The self-adhesive protective film according to claim 2, wherein the additive comprises 1 to 30% by weight of a release agent and 0 to 29% by weight of an antiblocking agent based on the total weight of the skin layer.
delete delete delete The self-adhesive protective film according to claim 2, wherein the core layer comprises at least one resin selected from the group consisting of polypropylene and polyethylene.
The self-adhesive protective film according to claim 2, wherein the adhesive layer comprises at least one resin selected from the group consisting of linear low density polyethylene, metallocene linear low density polyethylene, metallocene polyethylene and an elastomer.